Field of the Invention
The disclosure generally relates to a near field communication (NFC) antenna, and more particularly, to an NFC antenna with isotropic and high-efficiency characteristics.
Description of the Related Art
With the progress of mobile communication technology, portable electronic devices, such as portable computers, mobile phones, tablet computers, multimedia players, and other hybrid functional mobile devices, have become more common. To satisfy user demand, portable electronic devices can usually perform wireless communication functions. Some functions cover a large wireless communication area; for example, mobile phones using 2G, 3G, and LTE (Long Term Evolution) systems and using frequency bands of 700 MHz, 850 MHz, 900 MHz, 1800 MHz, 1900 MHz, 2100 MHz, 2300 MHz, and 2500 MHz. Some functions cover a small wireless communication area; for example, mobile phones using Wi-Fi, Bluetooth, and WiMAX (Worldwide Interoperability for Microwave Access) systems and using frequency bands of 2.4 GHz, 3.5 GHz, 5.2 GHz, and 5.8 GHz.
A mobile device with the near field communication (NFC) function, for example, has an NFC antenna which is often designed in a rectangular card and also has a rectangular shape to fit the card. This design may cause the related reader to be incapable of receiving signals from the NFC antenna at all angles. For example, when the angle between the reader and the long side of the NFC antenna is set to 90 or 270 degrees, the reader may receive a relatively weak electric field, and it therefore degrades the communication quality of the NFC antenna.